PURPOSE OF THE WORKSHOP
The George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES), supported by the National Science Foundation (NSF), is an important component of the National Earthquake Hazards Reductions Program (NEHRP). NEHRP is a coordinated effort across four federal agencies to address earthquake risk in the United States. Since 2004, NEES researchers have produced significant advances in the science and technology for earthquake loss reduction that would not have been possible without the network’s experimental facilities and cyberinfrastructure. By Fiscal Year 2014, NSF will have supported 10 years of NEES operations and research.
As part of NSF’s preparation of plans for Fiscal Year 2014 and beyond, NSF sought input from the broad earthquake engineering community on “Grand Challenges in Basic Earthquake Engineering Research,” with one consideration being that the program after 2014 need not be focused on—or limited to—existing facilities. At the request of NSF (see Statement of Task, Box S.1), the National Research Council (NRC) hosted a two-day workshop to give members of the community an opportunity to identify grand challenges and to describe networks of earthquake engineering experimental capabilities and cyberinfrastructure tools that could contribute to addressing these challenges.
An NRC steering committee was established to organize the workshop, which was held on March 14–15, 2011, at the NRC’s Beckman Center in Irvine, California. Workshop participants included 37 researchers and practitioners, drawn from a wide range of disciplines, to focus on the two key questions in the task statement. In addition, observers from NSF, NSF contractors, NEHRP, and the current NEES Operations Center attended the discussions. Altogether, there were 52 workshop attendees, including the committee and NRC staff (Appendix C).
The committee organized the workshop into a series of keynote presentations, breakout sessions, and plenary sessions. Six keynote speakers were tasked with articulating, through their presentations and associated white papers (Appendix B), a vision that would help guide discussions among the workshop participants. Each speaker discussed a key component of earthquake engineering research—community, lifelines, buildings, information technology, materials, and modeling and simulation—and considered four cross-cutting dimensions—community resilience, pre-event prediction and planning, design of infrastructure, and post-event response and recovery. Breakout sessions were the primary mechanism for brainstorming, analyzing, and documenting responses to the workshop questions outlined in the task. Four breakout sessions were structured along the cross-cutting dimensions, and one breakout session organized participants along disciplinary lines—buildings, lifelines, geotechnical/tsunamis, and community resilience. Each breakout session included a moderator, who served as the leader and chief spokesperson for the breakout group, and a committee member who served as rapporteur.
SUMMARY OF WORKSHOP DISCUSSIONS
This report summarizes the major points and ideas expressed during the workshop. It is not intended to be a comprehensive summary of all topics and issues relevant to earthquake engineering research. The observations or views contained in this report are those of individual participants and do not necessarily represent the views of all workshop participants, the committee, or the NRC. Therefore, references in the report to workshop “participants” do not imply that all participants were polled or that they necessarily agreed with the particular statements. In addition, the grand challenge problems and networked facilities discussed in the following sections were suggested by breakout group participants and they do not represent conclusions or recommendations of the committee or the NRC.
Statement of Task
The National Science Foundation (NSF) supports the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES), as a component of the National Earthquake Hazards Reduction Program (NEHRP). In Fiscal Year (FY) 2014, NSF will have supported 10 years of NEES operations and research, and seeks an evaluation of next-generation U.S. needs for earthquake engineering research beyond 2014. A National Research Council committee will organize a public workshop on the Grand Challenges for earthquake engineering research, to bring together experts to focus on two questions:
- What are the high-priority Grand Challenges in basic earthquake engineering research that require a network of earthquake engineering experimental facilities and cyberinfrastructure?
- What networked earthquake engineering experimental capabilities and cyberinfrastructure tools are required to address these Grand Challenges?
The workshop will feature invited presentations and discussion. The committee will develop the agenda, select and invite speakers and discussants, and moderate the discussion. Workshop participants will be asked to describe the experimental infrastructure capabilities and cyberinfrastructure tools in terms of requirements, rather than by reference to any existing or specifically located future facilities.
In responding to the foregoing questions, workshop participants will also be asked to consider future technical and conceptual advances with the potential to influence future earthquake hazard research, such as early warning systems, new materials, sustainability, high-performance computing and networking, modeling, sensor and monitoring technologies, and other factors identified by the committee. The committee will prepare a report summarizing discussions at the workshop; the report will not include findings or recommendations.
Grand Challenges in Earthquake Engineering Research
Grand challenges in earthquake research are the problems, barriers, and bottlenecks in the earthquake engineering field that hinder realization of the NEHRP vision—“A nation that is earthquake resilient in public safety, economic strength, and national security” (NEHRP, 2008). As such, they define frontiers in basic earthquake engineering research that would be needed to provide transformative solutions for achieving an earthquake-resilient society.
Thirteen grand challenge problems emerged over the course of the workshop. The committee has summarized them in terms of five overarching Grand Challenges, described below, in order to capture interrelationships and crossovers among the 13 problems and to highlight the interdisciplinary nature of their potential solutions. Participants noted that grand challenge problems do not stand alone; they are complex, and this complexity exists not only within earthquake engineering but also in earthquake engineering’s position among other competing social challenges. As such, addressing a grand challenge problem involves consideration of a variety of barriers—economic, regulatory, policy, societal, and professional—along with the scientific and technological solutions. The five overarching Grand Challenges are intended to serve as useful focal points for discussions among stakeholders and decision makers planning future investment toward achieving a more earthquake-resilient nation.
1. Community Resilience Framework: A common theme noted by participants was that the earthquake engineering community currently lacks an interactive and comprehensive framework for measuring, monitoring, and evaluating community resilience. Such a framework could apply innovative methodologies, models, and data to measure community performance at various scales, build on the experience and lessons of past events, and help ensure that past and future advances in building, lifelines, urban design, technology, and socioeconomic research result in improved community resilience. Such a framework also could advance our understanding of both the direct and indirect impacts of earthquakes so that community-level interactions and impacts can be better characterized.
2. Decision Making: Another sentiment reiterated during the workshop was that current research findings related to community resilience do not adequately influence decisions and actions on the part of key decision makers, such as private-sector facility owners and public-sector institutions. Communities typically build based on traditional standards, and when affected by major earthquakes, they respond and recover based on intuition, improvisation, and adaptive behaviors
that are drawn from the individuals available to participate. Consequently, the lessons learned in one community and event rarely translate to the next community affected. Participants suggested that achieving earthquake resilience could involve a community-based, holistic approach that includes decisions and actions that are based on overarching goals, a clear understanding of the built environment, rapid and informed assessment data, and planned reconstruction and recovery. Mechanisms for motivating action could include developing incentives to promote community development and pre-event planning; simulation-based decision-making strategies for use in community development, pre-event planning, in early response post event, and through the long-term recovery process; state-of-the-art decision-making tools that will lead to more efficient resource allocations; and methodologies and tools that allow decision makers to compare different strategies for post-earthquake reconstruction and long-term pre-earthquake mitigation.
3. Simulation: Participants noted that knowledge of the inventory of infrastructure components and points of connection between different infrastructure types is lacking within the earthquake engineering community. They identified a need for scalable tools that autonomously create an accurate database of all infrastructure components, including points of interdependency with other infrastructure components. Empowered with this complete mapping of an urban region’s infrastructure systems, powerful simulation technologies could model the time and spatial impacts of a seismic event at all length scales spanning from the component scale to the regional scale, and from disaster response to community recovery.
4. Mitigation: A large earthquake or tsunami in a highly populated region of the United States would cause massive damage to the built environment and communities in the region, and the resulting social and economic consequences would cascade across the country, particularly if major energy, transportation, or supply hubs are affected. Key characteristics of this Grand Challenge include developing strategies to measure, monitor, and model community vulnerability, motivations, and mitigation strategies, and establishing mitigation solutions for the community’s most vulnerable sectors. Participants suggested that mitigation solutions could be based on the use of a new generation of simulation tools and design solutions coupled with up-to-date information available from distributed sensing systems. Development of better approaches for renewal and retrofit of the built environment’s most vulnerable sectors would help ensure a safer environment and a more resilient community.
5. Design Tools: Participants suggested that developing and exploiting new emerging materials and innovative structural concepts and integrating them within design tools could dramatically improve the performance of all types of infrastructure and increase earthquake resilience in ways that are also sustainable. There is a wide range of sustainable, highly resilient, new materials that can offer opportunities to significantly change the way infrastructure is designed and constructed. Harnessing the power of performance-based earthquake engineering could achieve a resilient infrastructure that incorporates these innovative new materials and structural systems.
Networks of Facilities
The second goal of the workshop was for participants to identify the general requirements for networked earthquake engineering experimental capabilities and cyberinfrastructure tools associated with addressing the grand challenge problems. The suggested experimental facilities cover testing and monitoring over a wide range of scales, loading regimes, boundary conditions, and rates on laboratory and field (in situ) specimens. Cyberinfrastructure tools are also important for capturing, analyzing, and visualizing experiments and for supporting the advanced simulations discussed in the workshop. Participants described 14 facilities that could contribute to solving the grand challenge problems:
1. Community resilience observatory: Such an observatory could encompass interlinked facilities that function as a laboratory without walls, integrating experimental testing and simulations with a holistic understanding of communities, stakeholders, decisions, and motivations.
2. Instrumented city: An instrumented testbed in a high-risk, urban environment could provide invaluable data about the performance of the community and allow unprecedented research on studying decision-making processes for development and calibration of comprehensive, community models.
3. Earthquake engineering simulation center: Such a center could bring together earthquake engineering researchers with experts in algorithm development, computational and statistical methods, and high-end computational and cloud development methodologies to enable transformative advances in modeling and simulation.
4. Earthquake engineering data synthesis center: Such a center could offer the research community a large-scale database system for ingesting data sources from a variety of sensor types including imaging, remote sensing, video, and information management systems.
5. Earth observation: Earth observation systems could provide an integration of continuous and multi-sensor (e.g., aerial, satellite, and unmanned aerial vehicle) observations of communities at various scales for the purpose of characterizing the physical attributes of communities and monitoring the effects of earthquakes (e.g., damage assessment and recovery).
6. Rapid monitoring facility: Such a facility could provide the earthquake engineering community with a suite of highly portable sensing and data acquisition tools that could be rapidly deployed to structures, geo-facilities, and lifelines to monitor their stability after seismic events.
7. Sustainable materials facility: Partnering with material science facilities could lead to the development and testing of new construction grade materials that are self-healing, capable of energy capture, or ultra-high strength, and to understand the use of sustainable materials for earthquake engineering applications. A sustainable materials facility could test these materials under the conditions they may experience when used in construction accounting for the influence of aging and degradation.
8. Networked geotechnical centrifuges: Networked geotechnical centrifuges, each including innovative capabilities for robotic manipulation and actuation within the centrifuge container during the experiment, could allow new types of experimental modeling of landslides (including submarine landslides), liquefaction, and tsunamis.
9. SSI shaking table: A large-scale, dynamic shaking table designed for soil-structure interaction (SSI) experiments could enable a significant throughput of SSI experiments to help advance knowledge of this crucial component of earthquake engineering.
10. Large-scale shaking table: Testing complete structures or full-scale subsystems in multiple directions could provide fundamental knowledge for understanding the response of actual construction and the contributions of lateral and gravity load resisting systems and non-structural systems, validating post-earthquake evaluation methods for damaged structures.
11. Tsunami wave simulator: Such a revolutionary new facility could combine a tsunami wave basin with the capability to shake the ground to simulate liquefaction and subsidence.
12. Advanced structural subsystems characterization facility: Such a facility could test full-sized or close-to-full-scale subsystems and components under fully realistic boundary and loading conditions, to replicate the effects of corrosion, accelerated aging, and fatigue, and have the capability for multi-axial loading, high-temperature testing, and high pressures. It could enable the development of more accurate structural models needed for characterization of subsystems, components, and materials.
13. Non-structural, multi-axis testing facility: A high-performance multi-axis facility could be developed with the frequency range and levels of motion to investigate and characterize the performance of non-structural elements (e.g., partitions) and other content (e.g., shelving, information technology equipment, lighting, electrical and mechanical equipment) in three dimensions within a building or other infrastructure.
14. Mobile facility for in situ structural testing: A suite of highly portable testing equipment in such a facility could include shakers, actuators, sensors, and high-resolution data acquisition systems that could enable structures, lifelines, or geotechnical systems to be tested in place.